Heterostructured multi-principal element alloys prepared by laser-based techniques

Heterostructured materials, featured by two or more distinct zones with unique properties and intricate interactions at hetero-zone boundaries, showcase a remarkable strength-ductility synergistic effect for achieving superior mechanical properties surpassing their conventional homogeneous counterparts. Benefiting from the basic characteristics, such as complex composition, high configurational entropy and local distortion, multi-principal element alloys offer a fruitful playground for creating diverse heterostructures. Laser-based techniques such as laser surface treatment and laser additive manufacturing provide facile solutions with advantages such as high-energy density, rapid solidification rate, and precise control over processed zones and shapes, making them promising for the advancement of heterostructured multi-principal-element alloys. This review primarily highlights the nanoscale microstructural characteristics of various heterostructured multi-principal element alloys fabricated by laser-based techniques, along with their enhanced mechanical properties and other relevant service attributes. Moreover, it sheds light on the challenges and opportunities in harmonizing microstructural features to optimize the mechanical behavior of heterostructured multi-principal element alloys for industrial applications.